Electric safety-lantern



1. F. MONAHAN.

ELECTRIC SAFETY LANTERN.

APPLICATION FILED NOV. 23.1915. 29

2 SHEETS-SHEET l.

1. F. MONAHAN.

ELECTRIC SAFETY LANTERN.

APPLICATION FILED NOV-23,1915.

W//Zffwz' i f @Iggy/em Patented J 11116 29, 1920.

2 sHEETsI-SHEET 2.

UNITED As'r.\'r r:s

PATENT OFFICE.

`JAMES F. MONAHAN, F NEWARK, NEW JERSEY, ASSIGNOR TO EDISON STORAGE BATTERY COMPANY, 0F WEST ORANGE,

NEW JERSEY.

'0 all lwhom it may concern: j

Be itknown that I, JAMES F. MoNAHAxIgI, a citizen of the United ,States and a resident of Newark, in the county of Essex and State of New Jersey; have invented certain new `and useful Improvements in Electric use,

Safety-Lanterns, of which the following is a description.

My invention relates, to electric safety lanterns, which, while adapted for general are espec1ally designed for use in mines, tunnels, powder magazines and other places where readily combustible gasjs or other materials of a highly combustible or ex losive nature are liable to be present. ihe principal object of my invention is to provide an improved lantern of this character and of such construction as to insure against the ignition of gases or other` comfy bustible materials thereby, especially in case of damage to the lantern, suc 1 as the breakin of the lamp thereof.

y invention also contemplates the provision of a lantern of simple and improved construction which may be easily and quickly assembled and taken apart and in which, when the same'is assembled, the

lamp and connections thereto are inaccessible. A

Other objects and features of my invention will be hereinafter more fully described and claimed.

' In order that my invention ma be more clearly understood, attention is irected to the accom anying drawings forming part of this speci cation, and in which:

Figure 1 represents a central cross sectional view, partly in elevation, of a preferred form of my improved lantern with the parts shown in normal operative position;

Fig. 2 is a front view of the lantern, partly broken away and partly in section, showing sume upon the breaking of the lamp bulb;

Fig. 3 i's a view of the lantern in side elevation; and I Fig. 4 is asectional view taken on line 4-4 of Fig. 3.

The same reference` characters are used l throughout the several views of the draw- Specioation o! Letters Patent.

the parts in the position they as- NEW JERSEY, A CORPORATION OF ELECTRIC SAFETY-LANTERN.

Patented June 29, 1920.

,Application led November 2.8, 1915. Serial INo. 62,981. L

the lamp casing which preferably comprises a substantially semispherical metallic,l re- Hector 2 having an open circular front and an opening 3 in the upper wall portion thereof; Reference character4 represents a hollow cylindrical member having'a lower outwardly flanged portion 5 adapted to closely fit the exteriorl yof the reflector 2 and which is suitably secured to the reflector 2 to form an air-tight joint therewith about the opening 3, as by means of rivets. 'Iehe member 4 provided with an upper end wall 6 havin an opening 7 in vertical alinement wit the opening 3 in the reflector. A hollow cylindrical contact member. 8 is secured -at its upper end to the wall 6 and extends downwardly through the opening 3 into the reflector 2. The upper end portion of contact member 8 is somewhat less in diameter than the opening 7 through which lit extends, and the contact member is rigidly secured to the wall 6 by means of a nut 9 threaded on the exterior thereof and a coacting collar 10 with which member 8 is provided. Washers or rings 11 of insulating material are disposed between the wall 6 and the nut 9 and collar 10, and form an air-tight joint between the member 8 and wall 6.

sleeve 15 threaded into the upper end portion of member 8 to rigidl secure the guide 12l to contact member 8. lings or washers 16 of insulating material separate the collar 13 from the shoulder 14 and sleeve 15, and serve to form an air-tight joint between member 8 and guide 12. A second contact member 17 preferably in the form of a long cylindrical rod, is slidably mounted in the guide 12 and is provided at its ends with collars 18 and 19 which respectively coact with a shoulder provided on the interior of the guide 12 and the lower end of the guide to l1mit the downward and upward movement of the rod 17 with respect l to the guide. A metallic ring 20 rests on the upper end of sleeve and its upper surface is engaged by a shoulder formed on a sleeve 21 of insulating material which is disposed between the sleeve 15 and the guide 12. The lower end of sleeve 21 bears on the upper ring or washer 16 while the upper end.

thereof is preferably flush with the upper end of guide 12. A headed member 22 threaded into the upper end portion of guide 12 serves to rigidly secure a metallic ring 23 in contact with the upper end of guide 12 and to render the upper end of guide 12 air-tight, and also coperates with ring 2 3 to fasten parts 20 and 21 in the position shown. A compressed coiled spring 24 is disposed in the guide 12 between the provided with an annular seat 27 for the edge portion of the end of the neck o f a lamp 28, to which edge portion one termmal of the lamp filament is connected.v The other terminal of the lamp filament is connected to the central portion of the end of the neck of the lamp, which portion is adapted to engage the lower end of contact member 17. 'lhe contact member 17 is biased by gravitv and the spring 24 to the position shown in F ig. 2, in which collar 18 thereof engages the shoulderv formed on the interior of the guide 12, and when in this position prevents the engagement of the neck of the lamp with the seat 27 of Contact member 8, and consequently the completion of the lampA circuit. The lamp, however, may be readily moved upwardly against the action of the spring pressed contact member 17 to the position shown in Fig. 1, in which position lof' the lamp the neck thereof will engage seat 27 of contact member 8 as well as the lower end of contact member 17, and

the lamp circuit will be closed. Lamp 28 is normally held under spring pressure in circuit closing position, as shown in Fig. 1, by means of a spring 29 of considerably greater strength than the spring 24, and preferably in the form of a curved resilient strip of metal, one end of which is suitably secured to the reflector 2, and the other end of which is provided with an eye 30 disposed below and in alinement with contact member 17 and engaging the nib 31 on the end of the lamp bulb.` The lamp circuit is over the following path r-from the source of current through one conductor, as 25, ring 20,

purpose which will presently appear.

sleeve 1.5, and contact member 8, Ito one terminal of the lamp, then through the lamp filament to the other terminal of the lamp, then through contact member 17 ,guide 12, or spring 24 and member 22, to ring 23, and then through conductor 26 back to the source of current.

The insulated conductors 25 and 26, for the greater part of their length, are inclosed or embedded in a cable 32 of insulating material, and are dis )osed adjacent the reflector 2 in a substantiallv right angular hollow casing or tubular member 35. Une arm of the member 35 is enlarged so as to fit over the reduced upper end portion of the cylindrical`member 4. The member 35 is removably connected to the member 4 by a pair of bayonet joints, the pins 36 of these 'jolnt's being secured to member 4 and the slots 37 thereof, for the reception of pins 36, being formed 'in the lower end of member 35. The other arm of member 35 is but a little larger in diameter than the cable 32 located therein and extends rearwardly from i the reflector 2.V A sleeve 38 is mounted on and suitably secured, as by soldering, to the end of the rearwardly extending arm of the tubular member 35, and said sleeve is provided on its exterior with a coarse thread. `As indicated at 39, the sleeve 38 and the corresponding end of member 35 are longitudinally slotted on the underf side forB a e.. yond the rear end of member 35 the cable 32 is. loosely disposed in a tubular casing 41, preferably consisting of a flexible metallic tube. rlhe tube or casing 41 is detachablyy secured to the tubular member 35 by means of a sleeve 42 formed with a thread engaging the thread on sleeve 38 and rotatably mounted on tube 41, the sleeve 42 being provided at one end with a shoulder or flange coacting with a collar 43 on one end of the tube 41 to prevent the sleeve. from being withdrawn from the latter.

In order that the lantern may be readily attached to a suitable support, such as' the leather bracket on the front of the well known miners cap, I provide the same with a metallic hook 33, referably in the form of an inverted U.-- 8

ne leg 44 ofthe hookA 33 is suitably secured at its lower end, as by riveting, to the rear of the reflector 2, and

at its other end said leg is provided with av forwardly extending portion 45 which is rigidly secured at its end, as by means of a rivet, to the member 4. .The other leg 46 of the hook 33 is somewhat resilient and is adapted to engage an opening provided therefor in the bracket on the miners cap. A locking member 47 is pivotally mounted at one end on the base of the inverted U- shaped hook 33 and is provided at its other end with 'a substantially rectangular'portion 48 which is U-shape in cross section and which is adapted to fit closely in the slots 39.0f member 35 and sleeve 38, as

shown in Fig.l 4. The arrangement of theparts is such that the rectangular portion 48 of member 47 can enter slots 39 only when members 4 and 35 are in such a relative position that the pins 36 of the bayonet joint connections between such parts are in engagement with the closed ends ofthe slots 37. It will be evident that when members 4 and 351are so relatively positioned and member 47 is moved so that the ortion 48 thereof engages the slots 39, sai members 4 and 35 will be locked against relative turning movement, -and consequently the disconnection of these members will be prevented until portionl 48 is removed from the slots 39. The legs of the U-shaped portion 48 are each provided on the upper surface with teeth 49 which, when member 47 is in v the position shown in. Fig. 1, face the front of the lantern. Teeth 49 are adapted to engage the cable 32 and force the same against the wall of member 35 and thereby prevent movement of the cable 32 and the conductors 25 and 26 inclosed therein in the casing The sleeve 42, when threaded on sleeve 38, is adapted to take over the portion 48 of member 47 and lock the same in operative position, as shown in Figs. 1 and 4. It will be apparent that with this construction, the strains on the cable 32 tending to move the same longitudinally in the casing 35, will not be communicated to the connections of conductors 25 and 26 with contact members 8 and 17, but will, through casing 35, member 47 and hook 33, be taken up by the parts of the lantern casing to which the casing 35 and hook 33 are connected. It will be obvious from the above that member 47 and sleeve 42 coperating therewith constitute unitary means which serve to prevent the relative turning movement of members 4 and 35 necessary to disconnect the same, and also to prevent longitudinal movement of cable 32 in casing 35 and strains on the connections between conductors 25 and 26 and the contact members 8 and 17.

The front of the reflector 2 is provided with a flat outstanding annular ange 50 and a flange or rim 51 extending rearwardly :from the flange 50. The front of the reflector is normally closed by a circular glass plate 52, a suitable sealing ring 34, preferably of rubber, being disposed between such plate and the flange 50. The plate 52 is held in position by a circular retaining member 53 provided with a flange 54 surrounding rim 51 of the reflector 2, and` a flange 55 disposed substantially at right angles to flange 54 and engaging the outer surface of the edge portion of plate 52. As shown in Fig. 3, the retaining member 53 is removably connected to reflector 2 by a plurality of bayonet joints, the pins 56 of said joints being secured to the reflector and the slots 57 thereof bei-ng formed 'in lthe flange 54 of member 53. The major portions of the slots 57 are inclined so that the pins 56 will coact therewith, during turning movement of member 53 with respect to reflector 2 in one direction, to exert a camaction and force member 53 and thereby the plate 52 bodily toward the reflector. his will compress the sealing ring 34 and form a tight joint betweenplate 52 and the front of the reflector.

Referring to-Fig. 3, reference character 58- represents a resilient member secured at one end to the inner surface of flange 51 and provided adjacent its other end with an outwardly 'extending projection 59 which normally extends through an opening therefor in `the flange, and a lateral projection or finger piece 60 extending rearwardly beyond the flange. The flange 54 is provided circumfercntially thereof with a plurality of slightly spaced openings 61, 62 and 63 into any one of which the projection 59 of resilient member 58 is adapted to automatically engage when the same registers with the opening for projection 59 in the rim or flange 51. The resilient element 58 with its projection 59 and the series of openings 61, 62 and 63 constitute means for automatically locking the casing member or reflector 2 and the member 53 together at any one of a number of predetermined points. in the relative rotary movement of such members. Consequently, it is assured that the retaining member 53 may be readily brought to and locked in aposition with respect to casing member 2 to securely hold the glass 52 against ring 34 with suflicient force to prop erly seal thefront of the casing member 2.

lt is apparent that if the bulb of lamp 28 is broken which would be liable to happen if the glass plate 52 is broken, the spring 29 would cease to act through the bulb of the lamp to hold the terminals of the lamp in engagement with contact lmembers 8 and 17, and gravity and the spring pressed contact member 17 would at once act to move the lamp away from the contact member 8 and thereby break the lamp circuit, as shown in Fig. 2. Consequently, the filament of the lamp would be immediately extinguished and there would be no danger lof the same igniting gases or other combustible material in the vicinity of the lantern.

It will be apparent that the lamp 28 may be readily inserted in the lantern in the position shown in Fig. 1, upon removing the glass plate 52, by engaging the nib 31 of the pressed contact member 17 and guiding the neck of the lamp to the seat 27 of contact member 8.- Consequently, when the lamp is broken, the same may be quickly and readily re laced. I

he lantern described herein is very simple and efiicient, is neat in appearance, and

of the parts thereof without any departure 'from t e spirit of the invention and the sccipe of the appended claims.

aving now described my invention, what I claim as new and desire to protect by Letters Patent is as follows 1. In an electric safety lantern, an electric circuit including an incandescent lamp, a hollow contact member' provided at one end with a seat for engagement with one terminal of said lamp, and a spring pressed contact 'member yslidably mounted within said hollow contact member and adapted to engage the other terminal of said lamp, and means engaging the lamp bulb and holding the lamp in opposition to the action of said spring pressed contact member in a position with its terminals respectively in engagement with the Spring pressed contact member and the seat of said hollow contact member, substantially as described.

2. In a device of the class described, a casing member, a hollow member connected at one end to said casing member and adapted to contain conductors leading from said "casing member, a relative turning movement of said members serving to disconnect said members, and means remote from the connectlon between sald members applied to one of said members and engageable with.

the other of said members only in a vpredetermined relative position of said members to lock the latter against such relative turning movement, substantially as described.

3. In a device of the class described, a casing member, a hollow member connected at one end to said casing member and adapted to contain conductors leading from said casing member, a relative turning movement of sald members serving to disconnect said members, and unitary means applied to said casing member and which, in a predetermined relative position of said members, is

engageable with said hollow member and .saidy conductors to prevent such relative turning movement of said members and movement of said conductors in said hollow member, substantially as described.

4. In a ydevice of the class described, a

' casing member, a hollow member connected at one end to said casing member and adapted to contain conductors leading from said casing member, a relative turning movement of said members serving to disconnect said members, means remote from the connection between said members appliedto said casing member which is engageable with said hollow'member only in a predeter- Vmined relative position of said members to prevent such relative turning movement of said members, and a device for locking said means in operative position, substantially as described.

5'. In a device of the classdescribed, a casing member, a hollow member connected at one end to said casing member and adapt-l ed to contain conductors leading from said casing member, a relative turning movement of said members' serving to disconnect said members, ,means applied to said casing member which, in a predetermined relative position of said members, is engageable with said hollow member to prevent such relative turning movement of said members, and a device mounted on said hollow member and adjustable thereon to engage and lock said means in operative tially as described.

6. In a device of the class described, a lamp casing, conductors leading therefrom, a tubular member containing said conductors and having at one end a bayonet joint connection with vsaid casing, said tubular member having an opening adjacent its other end, and a device connected to said casing, said device, in a predetermined relative position of said casing and tubular member, being engageable with said opening and the conductors in said tubular member to hold the conductors against movement in ysaid tubular member and to lock said casing and tubular member against relative turning movement, substantially as described.

7. In a device of the class described, a lamp casing, conductors leading therefrom, a tubular member containing said conductors and having at one end a bayonet joint connection with said casing, said tubular member having an opening adjacent its other end, a device movably connected to said casing, said device in a predetermined relative position of said casing and tubular member, being movable to engage said opening and theJ conductors in said tubular member to hold the latter against movement in said tubular member and to lock said casing and tubular member against relative turning movement, and a sleeve mounted on the exterior of said tubular member and adapted to engage over said device to lock the same in operative position, substantially as described. 1

8. In a device of the class described, a lamp casing, conductors leading therefrom, a hollow member removably secured to said position, substancasing and containing saidconductors, and unitary means for locking said hollow member to said casing and for preventing movement of said conducto-rs in said member, substantially as described.

9. In an electric safety lantern, an electric circuit including an incandescent lamp, a contact member having a seat for engagement With one terminal of said lamp, and a slidable spring pressed contact member adapted to engage the other terminal of said lamp, one of said contact members being mounted Within the other contact member, and means for holding the lamp tion to the action. of said springpressed contact member in a position with its terminals respectively in engagement with the spring-pressed contact member and the Seat of the other contact member, substantially as described. i

10. In an electric safety lantern, an electric circuit including an incandescent lamp, a contact member having a seat for engagement with one terminal of said lamp, and a slidable spring pressed contact member adapted to engage the other terminal of said lamp, one of said contact members being mounted Within the other contact means for holding the lamp in opposition to the action of said spring-pressed contact member in a position with its terminals respectively in engagement with the springpressed contact member and the seat of the other contact member, and a guide for said slidable contact member, said guide being in opposi-` member,

removably applied to the other contact member, substantially as described.

11. In a casing member, a hollow member connected to said casing member and adapted to contain conductors leading from the casing member, a relative turning movement of said members serving to disconnect the same, and unitary means applied to one of sai members and which, in a predetermined relative position of said members, is engageable with the other of said members and said conductors to prevent such relative turning movement of said members and movement of said conductors in one of said members, substantially as described.

12. In a device of the classv describcd,fa casing member, a hollow member connected to said casing member and adapted to contain conductors leading from the casing member, a relative turning movement of said members serving to disconnect the same, means applied to one of said members which, in a predetermined relative position of said members, is engageable with the other of said members to prevent such rela tive turning movement of said members, and a device for locking said means in operative position, substantially as described.

VThis specification signed and witnessed this 19th day of November, 1915.

JAMES F. MONAHAN. Vitnesses:

WILLIAM A. HARDY, FREDERICK BACHMANN.

device of the class described, a i 

